Rigging with the bulls18 December 2018
Bull rigging is easy to recognise but hard to define as a way of moving a load. Perhaps that is why there is a growing shortage of skilled bull riggers. Julian Champkin tries to pin down the elusive subject.
The crane has got the load as far as it can. The jib may be at the end of its reach, there may be an obstacle to moving the crane body, there may be an overhang, or the destination may be in a confined interior space with little or no headroom, while the load is a large module that needs to be manoeuvred into it. Moving the load that last bit that the crane cannot manage— that, essentially, is bull rigging.
Even so, it lacks a clear definition. “Heavy lifting without a crane. That is how I define it,” says Joel Oliva, director of operations at NCCCO, the body which certifies bull riggers in the US.
“Bull rigging is a term used to refer to the lifting, moving or manipulation of objects by means other than cranes or crane-like lifting systems or conventional transport devices,” says Keith Anderson, chief rigging engineer at Bechtel. “It is a term for moving a large item from one position to another either inside or in an area where cranes cannot be used,” says Paul Barber, managing director of Rapid Response solutions.
Yet the NCCCO’s video on the certification of bull riggers shows the applicant lifting and rotating loads slung from an overhead hoist. So too does the video from training company ITI, which offers courses in bull rigging. Clearly the absence of a lifting device is not obligatory.
“Typically bull rigging involves a custom-arranged application of multiple items of rigging and mechanical devices such as chain falls, come-a-longs, rollers, skates, jacks, winches and rigging blocks used in concert,” says Anderson. It includes many sub-sets of skills that have other names: there is hand rigging; there is drifting, which is passing a payload through a building, rotating it, upending it or manipulating a large object through an opening; there is even Tarzaning— which is passing a payload from a crane to one or more chain hoists. “Bull rigging also includes using jacks to lift the load and then placing skates, castors or rollers under the load and manually moving it from one position to another. Or you can assist the push using winches, tirfors and hold backs. In hydraulic skidding the load is jacked up so track and skid shoes can be placed under it; then hydraulic rams push the load along,” says Barber.
So, depending on situation and size of load, bull rigging can be as simple as a man on the ground pushing the suspended load a foot or two to the side or as complex as a full-scale operation with 500t-capacity hydraulic jacks, skidding systems, several weeks of planning and a cast of dozens to carry it out. Skid-system loads typically range from 100t to 1,000t. Given such a huge variation and range it is little wonder that a formal definition of bull-rigging is elusive; but, as Anderson recently pointed out at the Specialized Carriers & Rigging Association (SC&RA) workshop in Kentucky, you know it when you see it.
However you choose to define or describe it, there is a growing need for bull rigging in mining, in power generation, in petro-chemicals, and in many other applications. The trend for pre-fabricating modules off-site means that larger and larger assemblies need to be moved into existing confined spaces. “Skidding and jacking has been around for many years, but it is becoming more commonplace as job sites are becoming more confined, with more overhead obstructions and safety restrictions,” says Janine Smith, vice-president of Hydra-Slide. “At the same time, the loads—be it a transformer, tunnel boring machine, generator or vessel—are becoming larger. In short, bigger, more complicated equipment is being handled in smaller, more complicated areas.”
Even when cranes are available, skidding and jacking may be a preferable solution. “One of the great things about these systems is that the weight, centre of gravity and footprint of the load really doesn’t matter as long as the cylinders and shoes aren’t overloaded. In comparison, the weight, size and CoG of a load is critical information when choosing a crane to mobilize,” says Smith.
The topic arose at the SC&RA workshop because Anderson was pointing not only to the expanding need for bull rigging, but also to the growing shortage of skilled bull riggers, the personnel who perform these sometimes extremely skilled and complex operations. The skilled operatives are reaching retirement age; few young people are coming up to replace them. That may be because they don’t know what it is; or it may be because it is so vague a term that the thought of specialising and training in it never occurs. In response the SC&RA, with ITI and Bechtel on board, has set up a task force to investigate the demand, training and skills set requirements for bull riggers.
Berard is a Lousiana-based company that specialises in heavy transport and rigging. A recent contract was to move the cut-off cabin and wheelhouse of a redundant tugboat onto dry land foundations on the banks of the Mississippi in Baton Rouge, Louisiana, where it was to be converted to serve as an office and interactive learning centre for students. The wheelhouse will be outfitted with controls and screens so that participants can visualise working as a captain on the vessel. The structure was 30m long by 18m wide and weighed 60,000lb (27t). It was originally intended to perform the lift with a 600t capacity floating crane. But falling river levels at the time of the lift meant that the crane could not get close to the bank and the final destination was out of reach of its jib.
Berard’s solution was to use a 300t capacity HT300 heavy-track skidding system from Canadian specialists Hydra-Slide. The wheelhouse was made to slide along the ground—or more precisely, along a specially-laid low-friction track—to its finally-desired position.
“A larger crane could have completed the task,” said Brett Berard, vice president of operations. “But it would have been far more expensive and time-consuming. Further, a quick turnaround was needed as the client was unaware of a solution to move the cabin from the crane radius to the foundations. We mobilised the Berard/Hydra-slide solution in only three days to avoid an additional reduction in river levels. We were on site for just one day.”
Such systems are not widely known outside the industry. “Most clients are over-thinking a solution,” said Berard. “They propose large cranes, or the infamous ‘mega heavy lift helicopter’—when in reality the apparently-simple skid solution is not only the safest but the most cost effective method of moving heavy cargo in confined spaces.”
The unit is the first of three that Berard has acquired from Hydraslide, and remains the company’s flagship product. A 500t capacity HT500 heavy-track and a 400t capacity LP400 low profile skidding system make up Berard’s fleet. “We first purchased the HT300 due to the simple design and the likely frequency of use; most cargo needing skid systems are less than 600,000lbs,” said Berard. “But the whole fleet has helped us to win contracts where we would not have been successful if we had presented other technologies as solutions. The myriad of benefits that we were able to offer the client in the old tugboat cabin move are testament to that.”
Not all loads are as unusual as a sawn-off tugboat cabin. P & L Machine Moving and Rigging in Johannesburg, South Africa used a bull rigging solution involving hydraulic jacks to move a skidmounted electrical transformer from the mine where it was used to a warehouse for refurbishment.
On average twice a year, P&L is asked to assist in moving electrical substations from local mines to its warehouse facility at Benoni, where they are overhauled and then returned to the mine.
For their most recent project, the refurbished 60t substation was too large to be loaded as normal onto the lowbed inside the warehouse. Instead it and its skid were moved to the warehouse exit using a 30t Pick and Carry machine and large machine moving axles. Once outside, to raise the skid higher for transporting, P&L lifted the skid with its four-leg Enerpac SBL500 hydraulic gantry, and the lowbed truck reversed underneath the skid which was then lowered onto the vehicle. The skid was transported to the colliery where it was offloaded with mobile cranes. The Enerpac SBL500 is part of the SBL-Series Super Boom Lift telescopic gantries and has a maximum lift capacity with four legs of 500t. It has selfcontained hydraulics and electronics, a wireless control system and selfpropelled wheels or tank rollers.
“We use the Enerpac SBL500 for a range of industrial lifting tasks where accurate lifting and positioning are essential. It gives us the flexibility we need for lifting projects where there is limited working space,” said Gareth Lucas, director of P & L.
“Bull rigging is a challenging category of load handling activities,” says Zack Parnell, president of ITI. “It is mainly performed by pipefitters, boilermakers, and maintenance personnel. We have found with several of our petrochemical and construction customers that personnel are not adequately trained and tested for this subset of rigging. That is why we are working with Bechtel to standardize this work process and why we have also enrolled the SC&RA to gain some consensus around definitions, personnel training and qualification guidelines, and responsibilities in the Bull Rigging Task Force within a safety committee at SC&RA.”
The scale of bull rigging operations varies hugely, from extreme projects like the two above to one man moving a small load from a hand-driven chain hoist as in the training and certification videos. This may be why there is such a lack of clarity in its definition and such haziness in the perception of it. Kraning is a training provider for Canadian bull riggers. “As for bull rigging being a popular training course, I have to say not really,” says company president Yannick Morin. “Because bull rigging is not well-known, most of our clients do not realize the importance of that specifi c training. The danger in bull rigging is not on the big jobs, because they have the resources to plan the job really well, but on smaller jobs or repetitive jobs. When you cohabit with the danger and you start to accept it and manage it, that is the specifi c moment when something bad happens.”
Anderson offers a similar point about large- and small-scale rigging: “SC&RA members perform this sort of work activity primarily in a maintenance capacity during plant shutdowns, while companies like Bechtel perform these activities more and more during new construction with the rise of modular construction techniques,” he says.
“Rigging is a job task performed by a variety of construction crafts as well as operations and maintenance personnel in plant environments,” he adds. “Bull rigging activities, and subsequently risk, is on the rise with modularization which requires teams to bring a payload—like a large valve, compressor, or pipe sections—into existing structures. This has always been a task for rigging experts like SC&RA members at power plants, refi neries and other plant environments, but we are seeing it more now in new construction.”
Even so, as Morin has said, it is not the most widely in demand. “One of the issues in the market is that suppliers give basic trainings for free when the client buys a system,” he says. “With that basic training, which is not under the scope of our Canadian laws for engineers, the client thinks his workers can plan and operate those load handling equipments.”
“Riggers need to be multiskilled,” says Barber. “They need to have a good practical knowledge of assessing & managing risk, as well as the ability to estimate the weight of loads and their C of G. Maths plays a big part in a rigger’s role, selecting slings, calculating sling angles and lengths and friction. And a rigger must be physically fi t as there is a great deal of manual handling involved.
“Crane operators may do the physical lifting but it is the riggers that calculate how to sling the load, what lifting tackle to use, where to place the slings and then give signals to the operator to ensure the load is lifted safely. The rigger coordinates all activities around the crane to maintain a safe lifting zone.”
“Frankly it is very specialised work,” says Oliva. “It is a small industry at the end of the day and one that is very advanced and that is ever more niche. ‘Bull rigging’ is a vernacular term, and I think that may affect how it is regarded.”
NCCCO is doing its part in identifying what riggers do and the skills that they need. “As a certifying body we play a very specifi c role. Certifi cation gives a credential. That is one way we protect specifi c areas in industry that need to be addressed” he says. “We break our rigger program into two distinct certifi cates: Level I and Level II. Level I is more fundamental: it covers basic practices: things like ‘know what you are lifting’ and ‘know if your equipment is the right capacity.’ Level II of the rigger’s exam is more what a lot of people might expect. It covers calculating assymetric loads, pick points, terminology, applications…”. The NCCCO prospectus states that a certified Level II rigger will be able, among other things, to estimate load weights and centres of gravity, identify lift points, understand load dynamics and associated hazards, and, as applicable, will also have a working knowledge of hoisting equipment, winches, jacks, industrial rollers, and similar equipment.
“It is a fundamental skill set that you need—no question of that,” says Oliva. The certification test, even for level II, centres on manipulating loads that can be lifted with a one-man operated chain hoist rather than anything bigger. Yet as we have seen, bull rigging loads can be very much larger.
“The range of scale is so massive” he says. “If you are inside a manufacturing plant the loads will be generally only a few pounds. But there are basic laws of physics and mathematics that you have to know to handle them safely. The same laws apply to much bigger loads, and mathematically you just add a few zeros to do the calculations; but large size really does take it up a scale. So certification is not like: ‘If you can do this you can do any rigging job.’ It is more a fundamental set of skills that you will need to operate both simple and more complex equipment.”
“And frankly, many cases are unique from one lift to the next. You cannot just apply a set of writtendown procedures. You have to think each project out.”
Which Barber echoes: “Even the most experienced riggers are continually learning and developing new skills.”
The NCCCO sees about a thousand people a year taking its level I riggers course; about 150 annually take level II, for which having passed Level I is a requirement.
“We have seen a significant increase in Level II interest,” says Oliva, “although these certifications are still considered voluntary.” Unlike the crane operator certification which is now becoming mandatory throughout the industry, there is as yet no immediate prospect of certification for riggers becoming mandatory.
“Though many big employers on the Gulf, petrochemical companies and the like, are now requiring certification for riggers,” he says. Safety consciousness is driving that; and the companies in turn are driving applications for both level I and level II certification. “But no requirement has reached the stage of legal regulation; except, strangely, in the city of Philadelphia. That is the one place where you do need a certificate to practice as a rigger.”
“There is a triangle in lifting and moving. The crane operator is the focus of attention; but the rigger and the signal person, are also there, and are also important.
“Again, a common image of bull rigging is a guy holding a rope and moving a suspended load a few feet to the right. For that reason it does not generally come top of development agendas. But we are expecting more and more attention to be paid to those other two corners of the triangle.”
It remains counter-intuitive that a load of many hundreds of tons can be simply slid along the ground. “Rollers, skids, unconventional movers that clever companies have invented—it is remarkable what they have created,” says Oliva. Their creations need skilled people to operate them and to think out the parameters of each move. So never mind the definition. Bull rigging and trained bull riggers are clearly needed.